Re: CVS commit: src/sys/sys

[Taylor R Campbell <riastradh%NetBSD.org@localhost>]

> Module Name:    src
> Committed By:   rillig
> Date:           Fri Apr  4 20:52:32 UTC 2025
> 
> Modified Files:
>         src/sys/sys: cdefs.h
> 
> Log Message:
> sys/cdefs.h: fix __predict_true and __predict_false for lint
> 
> -#define	__predict_true(exp)	__builtin_expect((exp) ? 1 : 0, 1)
> -#define	__predict_false(exp)	__builtin_expect((exp) ? 1 : 0, 0)
> +#define	__predict_true(exp)	__builtin_expect(/*CONSTCOND*/(exp) ? 1 : 0, 1)
> +#define	__predict_false(exp)	__builtin_expect(/*CONSTCOND*/(exp) ? 1 : 0, 0)

This seems wrong to me.  Why should we tell lint that _every_ input to
__predict_true/false is constant?

What lint objected to in this case is that ALIGNED_POINTER(...) is
always 1 on x86.  But it's not always 1 on all architectures.